[Amini77]

Originally Posted by Rival

THIS

plus ditch the run flats... you will save 10-13lbs from each wheel. If you dont get a muffler just delete it as a whole....... that will save 35lb. and with the 2nd cats + resonator its not bad, exhaust note wise/sound.


theres a thread here where a guy made is US airbox into a Euro box... basically you put a cone type filter in instead of the flat one that the US uses.

last, the 3 stage intake manifold from a 2006 330i of 530i.

The manifold, AA tune, headers are the big power gains... 10-15rwhp each.

the intake, muffler are prolly 4-7rwhp gains. the scoups only help once your doing 60mph +

This DIY:
http://www.e90post.com/forums/showthread.php?t=626376